Enhancing Psychosis Risk Prediction Through Computational Cognitive Neuroscience
AbstractResearch suggests that early identification and intervention with individuals at clinical high risk (CHR) for psychosis may be able to improve the course of illness. The first generation of studies suggested that the identification of CHR through the use of specialized interviews evaluating attenuated psychosis symptoms is a promising strategy for exploring mechanisms associated with illness progression, etiology, and identifying new treatment targets. The next generation of research on psychosis risk must address two major limitations: (1) interview methods have limited specificity, as recent estimates indicate th...
Source: Schizophrenia Bulletin - July 10, 2020 Category: Psychiatry Source Type: research
Hallucinations in Older Adults: A Practical Review
AbstractOlder adults experience hallucinations in a variety of social, physical, and mental health contexts. Not everyone is open about these experiences, as hallucinations are surrounded with stigma. Hence, hallucinatory experiences in older individuals are often under-recognized. They are also commonly misunderstood by service providers, suggesting that there is significant scope for improvement in the training and practice of professionals working with this age group. The aim of the present article is to increase knowledge about hallucinations in older adults and provide a practical resource for the health and aged-care...
Source: Schizophrenia Bulletin - July 8, 2020 Category: Psychiatry Source Type: research
Multiple Network Dysconnectivity in Adolescents with Psychotic Experiences: A Longitudinal Population-Based Study
AbstractAbnormal functional connectivity (FC, the temporal synchronization of activation across distinct brain regions) of the default mode (DMN), salience (SN), central executive (CEN), and motor (MN) networks is well established in psychosis. However, little is known about FC in individuals, particularly adolescents, reporting subthreshold psychotic experiences (PE) and their trajectory over time. Thus, the aim of this study was to investigate the FC of these networks in adolescents with PE. In this population-based case-control study, 24 adolescents (mean age = 13.58) meeting the criteria for PE were drawn from a sample...
Source: Schizophrenia Bulletin - July 2, 2020 Category: Psychiatry Source Type: research
Antipsychotic Medications: Flawed Concepts and Ethics
In a previous editorial, one of us (W.T.C.) tweet-styled “Things I do not like” ranging from what is wrong with Positive and Negative Syndrome Scale (PANSS) total scores, what to do with first degree relatives, stigma, P-values and a brief tweet on ethics of antipsychotic (AP) clinical trials.1 Two of us now provide here a new list of things we do not like related to how our field conceptualizes AP medications and conducts research to evaluate their efficacy. This time a more on the ethics of placebo-controlled AP trials. (Source: Schizophrenia Bulletin)
Source: Schizophrenia Bulletin - June 23, 2020 Category: Psychiatry Source Type: research
Promoter Activity-Based Case-Control Association Study on SLC6A4 Highlighting Hypermethylation and Altered Amygdala Volume in Male Patients With Schizophrenia
We examined CpG sites ofSLC6A4, whose DNA methylation levels have been reported to be altered in bipolar disorder, using 3 independent cohorts of patients with SZ and age-matched controls. We found significant hypermethylation of a CpG site inSLC6A4 in male patients with SZ in all 3 cohorts. We showed that chronic administration of risperidone did not affect the DNA methylation status at this CpG site using common marmosets, and that in vitro DNA methylation at this CpG site diminished the promoter activity ofSLC6A4. We then genotyped the 5-HTT-linked polymorphic region (5-HTTLPR) and investigated the relationship among 5-...
Source: Schizophrenia Bulletin - June 19, 2020 Category: Psychiatry Source Type: research
Meta-Analysis of Sensorimotor Gating Deficits in Patients With Schizophrenia Evaluated by Prepulse Inhibition Test
AbstractsPrepulse inhibition (PPI) of startle is an operational measure of sensorimotor gating that is often impaired in patients with schizophrenia. Despite the large number of studies, there is considerable variation in PPI outcomes reported. We conducted a systematic review and meta-analysis investigating PPI impairment in patients with schizophrenia compared with healthy control subjects, and examined possible explanations for the variation in results between studies. Major databases were screened for observational studies comparing healthy subjects and patients with schizophrenia for the prepulse and pulse intervals o...
Source: Schizophrenia Bulletin - June 7, 2020 Category: Psychiatry Source Type: research
The Trace Kynurenine, Cinnabarinic Acid, Displays Potent Antipsychotic-Like Activity in Mice and Its Levels Are Reduced in the Prefrontal Cortex of Individuals Affected by Schizophrenia
AbstractCinnabarinic acid (CA) is a kynurenine metabolite that activates mGlu4 metabotropic glutamate receptors. Using a highly sensitive ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS-MS) method, we found that CA is present in trace amounts in human brain tissue. CA levels were largely reduced in the prefrontal cortex (PFC) of individuals affected by schizophrenia. This reduction did not correlate with age, sex, duration of the disease, and duration and type of antipsychotic medication and might, therefore, represent a trait of schizophrenia. Interestingly, systemic treatment with low doses of C...
Source: Schizophrenia Bulletin - June 7, 2020 Category: Psychiatry Source Type: research
Cortical Volume Differences in Subjects at Risk for Psychosis Are Driven by Surface Area
AbstractIn subjects at risk for psychosis, the studies on gray matter volume (GMV) predominantly reported volume loss compared with healthy controls (CON). However, other important morphological measurements such as cortical surface area (CSA) and cortical thickness (CT) were not systematically compared. So far, samples mostly comprised subjects at genetic risk or at clinical risk fulfilling an ultra-high risk (UHR) criterion. No studies comparing UHR subjects with at-risk subjects showing only basic symptoms (BS) investigated the differences in CSA or CT. Therefore, we aimed to unravel the contribution of the 2 morphometr...
Source: Schizophrenia Bulletin - May 28, 2020 Category: Psychiatry Source Type: research
Paracingulate Sulcus Length Is Shorter in Voice-Hearers Regardless of Need for Care
AbstractHallucinations —while often considered an indication of mental illness—are commonly experienced by those without a need for clinical care. These nonclinical voice-hearers offer an opportunity to investigate hallucinations in the absence of confounds inherent to the clinical state. Recent work demonstrates an a ssociation between auditory verbal hallucinations (AVH) and structural variability in paracingulate sulcus (PCS) of medial prefrontal cortex in a clinical population. However, before PCS length may be considered a biomarker for clinical hallucination risk, it is necessary to investigate PCS structur e in ...
Source: Schizophrenia Bulletin - May 20, 2020 Category: Psychiatry Source Type: research
Impairments in Probabilistic Prediction and Bayesian Learning Can Explain Reduced Neural Semantic Priming in Schizophrenia
AbstractIt has been proposed that abnormalities in probabilistic prediction and dynamic belief updating explain the multiple features of schizophrenia. Here, we used electroencephalography (EEG) to ask whether these abnormalities can account for the well-established reduction in semantic priming observed in schizophrenia under nonautomatic conditions. We isolated predictive contributions to the neural semantic priming effect by manipulating the prime ’s predictive validity and minimizing retroactive semantic matching mechanisms. We additionally examined the link between prediction and learning using a Bayesian model that...
Source: Schizophrenia Bulletin - May 20, 2020 Category: Psychiatry Source Type: research
Clozapine Combination and Augmentation Strategies in Patients With Schizophrenia —Recommendations From an International Expert Survey Among the Treatment Response and Resistance in Psychosis (TRRIP) Working Group
ConclusionsGiven the limited evidence from randomized trials of treatment strategies for clozapine-resistant schizophrenia (CRS), this consensus-based series of recommendations provides a framework for decision making to manage this challenging clinical situation. (Source: Schizophrenia Bulletin)
Source: Schizophrenia Bulletin - May 18, 2020 Category: Psychiatry Source Type: research
Association Between Childhood Green Space, Genetic Liability, and the Incidence of Schizophrenia
AbstractChildhood exposure to green space has previously been associated with lower risk of developing schizophrenia later in life. It is unclear whether this association is mediated by genetic liability or whether the 2 risk factors work additively. Here, we investigate possible gene –environment associations with the hazard ratio (HR) of schizophrenia by combining (1) an estimate of childhood exposure to residential-level green space based on the normalized difference vegetation index (NDVI) from Landsat satellite images, with (2) genetic liability estimates based on polygeni c risk scores for 19 746 genotyped individu...
Source: Schizophrenia Bulletin - May 16, 2020 Category: Psychiatry Source Type: research
Antipsychotic Dose in Acute Schizophrenia: A Meta-analysis
AbstractLittle is known regarding optimal antipsychotic doses in the acute phase of schizophrenia. The aim of the present study was to employ the concept of minimum effective dose (MED) in examining efficacy and tolerability within this population. MED was identified for each antipsychotic through a previous systematic review. We then identified double-blind placebo-controlled randomized trials that involved fixed-dose antipsychotic monotherapy in acute schizophrenia and compared the identified MED vs higher doses of the same oral antipsychotic. Studies were selected from a recent meta-analysis examining dose –response r...
Source: Schizophrenia Bulletin - May 16, 2020 Category: Psychiatry Source Type: research
Interrelationships Between BDNF, Superoxide Dismutase, and Cognitive Impairment in Drug-Naive First-Episode Patients With Schizophrenia
AbstractThe pathogenesis and etiology of schizophrenia (SCZ) remains unclear. Accumulating studies showed that complex interrelationships between brain-derived neurotrophic factor (BDNF) and an imbalanced redox system has a crucial role in the psychopathology of SCZ. However, the influence of the interrelationships of BDNF and superoxide dismutase (SOD) on cognitive impairment and clinical symptomatology in drug-naive first-episode (DNFE) SCZ patients has not been studied thoroughly. Serum BDNF levels, plasma total SOD, manganese-SOD (Mn-SOD), copper/zinc-containing SOD (CuZn-SOD) activities, and malondialdehyde (MDA) leve...
Source: Schizophrenia Bulletin - May 11, 2020 Category: Psychiatry Source Type: research
AVATAR Therapy for Distressing Voices: A Comprehensive Account of Therapeutic Targets
This article presents, for the first time, the full range of therapeutic targets along with information on acceptability and potential side effects. Interest in the approach is growing rapidly and this report acts as a necessary touchstone for future development. (Source: Schizophrenia Bulletin)
Source: Schizophrenia Bulletin - May 6, 2020 Category: Psychiatry Source Type: research
